| Swansea to Ickenham | 4,181.87 mi (6,730.06 km) |
| Swansea to Ifield | 4,204.48 mi (6,766.46 km) |
| Swansea to Ilford | 4,202.47 mi (6,763.22 km) |
| Swansea to Ilfracombe | 4,048.61 mi (6,515.61 km) |
| Swansea to Ilkeston | 4,107.09 mi (6,609.72 km) |
| Swansea to Ilkley | 4,060.68 mi (6,535.03 km) |
| Swansea to Immingham | 4,129.18 mi (6,645.27 km) |
| Swansea to Ince-in-Makerfield | 4,042.33 mi (6,505.50 km) |
| Swansea to Inverness | 3,881.80 mi (6,247.16 km) |
| Swansea to Inverurie | 3,950.87 mi (6,358.31 km) |
| Swansea to Ipswich | 4,227.79 mi (6,803.97 km) |
| Swansea to Irlam | 4,051.64 mi (6,520.48 km) |
| Swansea to Irthlingborough | 4,152.47 mi (6,682.75 km) |
| Swansea to Irvine | 3,911.36 mi (6,294.73 km) |
| Swansea to Islington | 4,195.62 mi (6,752.20 km) |
